Structural Naming of nAChRs

[DanSandberg]

I'm studying nAChR proteins, such as nAChBP or the torpedo EM nAChR. The structure is quite complex IMO and the jargon can get somewhat taxing. For example, an article I'm reading presently claims that human nAChRs in membrane of nerve cells have an (Alpha)2(Beta,Gamma,Delta) quaternary structure in the embryonic form and (Alpha)2(Beta,Epsilon,Delta) in the adult.

Firstly, does embryonic/adult refer to the host organism, i.e. the human?

Secondly, my impression was the alpha subunits were CLR proteins with receptor sites and the Beta, Gamma, Delta subunits were 3 other CLR proteins without receptor sites. Does the distinction between Beta, Gamma, Delta and Beta, Epsilon, Delta simply imply that there is some structural or chemical change to the Gamma subunit from embryonic to adult or is there an actual meaning to the term "Gamma" over "Epsilon"? If there is simply a change from embryonic to adult then this paper is vague.

[JackBean]

look into hemoglobin (or heamoglobin, if you like). It's composition also changes during the development. It has meaning due to different oxygen affinities.
However, I don't know your proteins, so I don't know, what could be the reasoning. Isn't in mentioned in the article?

[DanSandberg]

no - unfortunately it is not. The simply state the receptor is an arrangement of 5 protein subunits, 2 alpha, one beta, one gamma, one delta. Then they later say delta becomes epsilon. No reference, no definition. I'll look into hemoglobin.